212
FXUS61 KPBZ 270806
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
406 AM EDT Thu Jun 27 2024

.SYNOPSIS...
Dry weather resumes today with shower and thunderstorm chances
returning for the weekend. Near normal temperatures today will
rise into the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
KEY MESSAGES:

- Patchy morning fog will lift by mid-morning.
- Dry weather resumes today with near normal temperatures.

-------------------------------------------------------------------

A moist, cool airmass after recent precipitation along with
relatively light wind and saturated low levels has resulted in
patchy fog development and low stratus this morning. Have issued
a SPS to cover this as no large scale sub 1/4 mile visibilities
have been seen in obs or area webcams. Any stratus or fog
should erode by mid- morning.

Cool, dry northwest flow as high pressure builds in from the
northwest along with increasing subsidence will diminish
lingering stratocu through the morning, which should eventually
turn into scattered afternoon cumulus. Cold advection and
partial cloud cover will result in more seasonable afternoon
temperature while post- frontal mixing may support NW wind gusts
around 20 mph.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
KEY MESSAGES:

- Dry weather continues.
- Temperature rises above normal again Friday.

-------------------------------------------------------------------

Surface high pressure transitions over New England and heights
rise ahead of the next upper level shortwave. Positioning of
the high will support weak warm, moist advection amid mostly
clear skies to raise area temperature about 5 degrees above the
daily average. Broad ascent may increase mid to high level
clouds and even low probability showers Friday night as a warm
front approaches.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
KEY MESSAGES:

- Shower and thunderstorm chances return Saturday into Sunday
  with the next low pressure system.
- Severe weather threat returns Saturday

-------------------------------------------------------------------

Broad ascent within warm, moist southwesterly flow ahead of the
main upper level trough will support increasing shower and
thunderstorm probabilities starting early Saturday morning as
the associated sfc low moves across the upper Great Lakes.
Saturday afternoon and evening is likely to be active with a
crossing shortwave and the cold front approaching from the west.

Severe weather will once again be a possibility as increasing
mid level flow overspreads an increasingly moist warm sector.
Latest ensembles show CAPE values from 1000-2000J/kg with
effective shear in between 30kts and 40kts. SPC has placed the
area under a Day 3 Slight Risk and CSUs machine learning output
shows 5% probs for both winds and tornadoes, which is not
surprising looking at forecast hodographs.

Dry weather and seasonable temperature is likely by late Sunday
into next week as the upper trough axis moves east and high
pressure builds in from the western Great Lakes.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
Little change was made to the 06Z TAFs for tonight with much of
the forecast still on track for some fog and low cloud
development tonight. Probabilities of IFR vis restrictions
remain highest to the west of KPIT with probabilities towards
60% due to anticipated clearing and recent rainfall. The
probabilities of IFR cigs remain highest (70% to 90%) east of
PIT, with plenty of moisture near the surface and nocturnal
cooling. Some combination of restrictions was noted for all
ports with lifting anticipated into the day. Broken decks are
favored just after sunrise. By afternoon, there is a 80% to 50%
probability that broken decks become scattered as we transition
to VFR boundary layer cumulus.

Cloud cover is expected to clear tomorrow night as mixing
ceases. This may lend to patchy MVFR vis restrictions late
overnight in fog. This remains most likely for river valley
ports and north of I-80.


.Outlook...

VFR is expected through Fri amid high pressure. Restrictions
are possible Fri night with a crossing warm front.

Restrictions are likely Sat and Sat night with showers and
thunderstorms ahead of and along a crossing cold front. VFR
returns Sun under high pressure.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.

&&

$$

SYNOPSIS...88
NEAR TERM...88
SHORT TERM...88
LONG TERM...Frazier/88
AVIATION...Milcarek